The invention relates to a method and system for processing navigation data and playing recorded audio compact disks using a shared compact disk device.
Navigation systems that provide a vehicle operator with directions to a desired destination are well known in the art. These systems typically employ a global positioning system (GPS) sensor to establish the current latitude and longitude of the vehicle or the exact location of a destination. Such systems also employ a compact disk (xe2x80x9cCDxe2x80x9d) mechanism or player to permit reading of compact disks on which road map information is stored. Using the information stored on the compact disk as well as the information reported by the GPS sensor, the navigation system can determine a route and provide directions to a desired destination.
Because many vehicle operators desire to listen to audio recordings on compact disk while operating their vehicle, the present invention provides the ability to use one compact disk player to read navigation information from a compact disk as well as for playing audio recordings from a compact disk.
DE 3,904,344 A1 discloses a method of reading navigation data from a compact disk, which is stored with a plurality of audio compact disks in a CD changer. The navigation data are read only during playback pauses of the audio disk, so that when playing audio disks, interfering interruptions are avoided.
Japanese Patent Publication Number JP-A-09-062 183 (D1) disclose a navigation mechanism and CD player, in which system data read from navigation data CD""s are stored in an intermediate memory so that the data CD can be removed from the CD player and replaced by an audio CD. Japanese Patent Publication Number JP-A-09 049 739 also discloses method and apparatus for reading all available navigation data respecting a trip destination from a CD and storing the information in an intermediate memory, thereby freeing the CD player for playback of audio compact disks. In each case, a disadvantage is that a very large intermediate memory is required.
These prior systems require complex components to enable the same CD player to read and play back both data and also audio CD disks.
An object of the present invention is to provide a method, and system for practicing the method, for reading navigation data from CD disks and for reading and playing back audio from CD disks, that can be practiced without resort to the complexity of the prior art technology.
In one preferred embodiment of the present invention, a method and system for performing the method are provided for displaying simplified directions to a desired destination and operating a shared compact disk reader, such as a CD-ROM drive. In a preferred embodiment, the method includes receiving destination information from a vehicle operator as well as current position information from a navigation sensor such as a GPS receiver. If map information on a compact disk is not available, such as when an audio compact disk is being played in the compact disk reader, a determination of simplified directions to the desired destination is made and the simplified directions are reported to the vehicle operator.
In another preferred embodiment, the simplified directions include directional information, geometric distance to the desired destination, and/or estimated road travel distance to the desired destination.
In yet another preferred embodiment, the simplified directions are visually displayed or acoustically reported to the vehicle operator.
In another preferred embodiment of the present invention, a single compact disk reader is connected via a controllable hardwired switch or via a controllable software switch alternatively to an audio system and to a navigation data processor. When the switch is set to pass information from the compact disk device to the navigation data processor, the processor is able to determine and report detailed directions to a desired destination. When the switch is set to pass information, such as audio recordings, from the compact disk device to the audio system, the navigation data processor determines and reports simplified directions to a desired destination. In this embodiment, the additional apparatus outlay required to use a single compact disk reader to read navigation data from one CD disk and also to playback audio recordings comprises no additional electronic means except the controllable switch.
The invention is described in detail below by reference to the accompanying drawing of a system which illustrates a preferred embodiment of the present invention and serves to explain the principles of the present invention. The drawing is incorporated and constitutes part of this disclosure. The scope of the invention is pointed out in the appended claims.